The ratio of male to female students is the amount of male students devided by the amount of female students.

\(\displaystyle\frac{{90}}{{110}}=\frac{{9}}{{11}}\)

\(\displaystyle\frac{{90}}{{110}}=\frac{{9}}{{11}}\)

Question

asked 2020-11-07

1)A rewiew of voted registration record in a small town yielded the dollowing data of the number of males and females registered as Democrat, Republican, or some other affilation:
\(\displaystyle{b}{e}{g}\in{\left\lbrace{a}{r}{r}{a}{y}\right\rbrace}{\left\lbrace{c}\right\rbrace}{G}{e}{n}{d}{e}{r}\backslash{h}{l}\in{e}{A}{f}{f}{i}{l}{a}{t}{i}{o}{n}&{M}{a}\le&{F}{e}{m}{a}\le\backslash{h}{l}\in{e}{D}{e}{m}{o}{c}{r}{a}{t}&{300}&{600}\backslash{R}{e}{p}{u}{b}{l}{i}{c}{a}{n}&{500}&{300}\backslash{O}{t}{h}{e}{r}&{200}&{100}\backslash{h}{l}\in{e}{e}{n}{d}{\left\lbrace{a}{r}{r}{a}{y}\right\rbrace}\)
What proportion of all voters is male and registered as a Democrat?
2)A survey was conducted invocted involving 303 subject concerning their preferences with respect to the size of car thay would consider purchasing. The following table shows the count of the responses by gender of the respondents:
\(\displaystyle{b}{e}{g}\in{\left\lbrace{a}{r}{r}{a}{y}\right\rbrace}{\left\lbrace{c}\right\rbrace}{S}{i}{z}{e}\ {o}{f}\ {C}{a}{r}\backslash{h}{l}\in{e}{G}{e}{n}{d}{e}{r}&{S}{m}{a}{l}{l}&{M}{e}{d}{i}{u}{m}&{l}{a}{n}\ge&{T}{o}{t}{a}{l}\backslash{h}{l}\in{e}{F}{e}{m}{a}\le&{58}&{63}&{17}&{138}\backslash{M}{a}\le&{79}&{61}&{25}&{165}\backslash{T}{o}{t}{a}{l}&{137}&{124}&{42}&{303}\backslash{h}{l}\in{e}{e}{n}{d}{\left\lbrace{a}{r}{r}{a}{y}\right\rbrace}\)
the data are to be summarized by constructing marginal distributions. In the marginal distributio for car size, the entry for mediums car is ?

asked 2021-03-06

Based on a sample of 80 recent Masters graduates (40 male and 40 female), the following information was made available regarding their annual salaries. The standard deviation of salaries for the male graduates was $40,000 and that for the female graduates was $25,000.

a) For the male graduates, what is the probability of obtaining a sample mean salary within $10,000 of the population mean?

b) Consider the same question in (a) but for the female graduates. In which case, males or females, do we have a higher probability of obtaining a sample estimate within $10,000 of the population mean? Why?

c) Suppose that the sample mean salary of females is $125,000. Develop a \(95\%\) confidence interval estimate for the mean salary of all female graduates

a) For the male graduates, what is the probability of obtaining a sample mean salary within $10,000 of the population mean?

b) Consider the same question in (a) but for the female graduates. In which case, males or females, do we have a higher probability of obtaining a sample estimate within $10,000 of the population mean? Why?

c) Suppose that the sample mean salary of females is $125,000. Develop a \(95\%\) confidence interval estimate for the mean salary of all female graduates

asked 2021-03-07

Personnel selection. Suppose that 6 female and 5 male applicants have been successfully screened for 5 positions. If the 5 positions are filled at random from the 11 finalists, what is the probability of selecting

(A) 3 females and 2 males?

(B) 4 females and 1 male?

(C) 5 females?

(A) 3 females and 2 males?

(B) 4 females and 1 male?

(C) 5 females?

asked 2020-11-01

Identify the appropriate hypothesis test for each of the following research situations using the options: The null hypothesis, The Test Statistics, The Sample Statistic, The Standard Error, and The Alpha Level.

A researcher conducts a cross-sectional developmental study to determine whether there is a significant difference in vocabulary skills between 8-year-old and 10-year-old children. A researcher determines that 8% of the males enrolled in Introductory Psychology have some form of color blindness, compared to only 2% of the females. Is there a significant relationship between color blindness and gender?

A researcher records the daily sugar consumption and the activity level for each of 20 children enrolled in a summer camp program. The researcher would like to determine whether there is a significant relationship between sugar consumption and activity level.

A researcher would like to determine whether a 4-week therapy program produces significant changes in behavior. A group of 25 participants is measured before therapy, at the end of therapy, and again 3 months after therapy.

A researcher would like to determine whether a new program for teaching mathematics is significantly better than the old program. It is suspected that the new program will be very effective for small-group instruction but probably will not work well with large classes. The research study involves comparing four groups of students: a small class taught by the new method, a large class taught by the new method, a small class taught by the old method, and a large class taught by the old method.

A researcher conducts a cross-sectional developmental study to determine whether there is a significant difference in vocabulary skills between 8-year-old and 10-year-old children. A researcher determines that 8% of the males enrolled in Introductory Psychology have some form of color blindness, compared to only 2% of the females. Is there a significant relationship between color blindness and gender?

A researcher records the daily sugar consumption and the activity level for each of 20 children enrolled in a summer camp program. The researcher would like to determine whether there is a significant relationship between sugar consumption and activity level.

A researcher would like to determine whether a 4-week therapy program produces significant changes in behavior. A group of 25 participants is measured before therapy, at the end of therapy, and again 3 months after therapy.

A researcher would like to determine whether a new program for teaching mathematics is significantly better than the old program. It is suspected that the new program will be very effective for small-group instruction but probably will not work well with large classes. The research study involves comparing four groups of students: a small class taught by the new method, a large class taught by the new method, a small class taught by the old method, and a large class taught by the old method.

asked 2021-02-12

A random sample of 1200 U.S. college students was asked, "What is your perception of your own body? Do you feel that you are overweight, underweight, or about right?" The two-way table summarizes the data on perceived body image by gender.

\(\begin{array}{c|c} & Female\ \ \ \ \ \ Male & Total \\ \hline About\ right & 560\ \ \ \ \ \ \ \ \ \ 295 & 855\\ \hline Overweight & 163\ \ \ \ \ \ \ \ \ \ 72 & 235 \\ \hline Underweight & 37\ \ \ \ \ \ \ \ \ \ \ \ 73 & 110 \\ \hline Total & 760\ \ \ \ \ \ \ \ \ \ 440 & 1200 \end{array}\)

What proportion of the sample is female?

\(\begin{array}{c|c} & Female\ \ \ \ \ \ Male & Total \\ \hline About\ right & 560\ \ \ \ \ \ \ \ \ \ 295 & 855\\ \hline Overweight & 163\ \ \ \ \ \ \ \ \ \ 72 & 235 \\ \hline Underweight & 37\ \ \ \ \ \ \ \ \ \ \ \ 73 & 110 \\ \hline Total & 760\ \ \ \ \ \ \ \ \ \ 440 & 1200 \end{array}\)

What proportion of the sample is female?

asked 2020-10-23

The table below shows the number of people for three different race groups who were shot by police that were either armed or unarmed. These values are very close to the exact numbers. They have been changed slightly for each student to get a unique problem.

Suspect was Armed:

Black - 543

White - 1176

Hispanic - 378

Total - 2097

Suspect was unarmed:

Black - 60

White - 67

Hispanic - 38

Total - 165

Total:

Black - 603

White - 1243

Hispanic - 416

Total - 2262

Give your answer as a decimal to at least three decimal places.

a) What percent are Black?

b) What percent are Unarmed?

c) In order for two variables to be Independent of each other, the P \((A and B) = P(A) \cdot P(B) P(A and B) = P(A) \cdot P(B).\)

This just means that the percentage of times that both things happen equals the individual percentages multiplied together (Only if they are Independent of each other).

Therefore, if a person's race is independent of whether they were killed being unarmed then the percentage of black people that are killed while being unarmed should equal the percentage of blacks times the percentage of Unarmed. Let's check this. Multiply your answer to part a (percentage of blacks) by your answer to part b (percentage of unarmed).

Remember, the previous answer is only correct if the variables are Independent.

d) Now let's get the real percent that are Black and Unarmed by using the table?

If answer c is "significantly different" than answer d, then that means that there could be a different percentage of unarmed people being shot based on race. We will check this out later in the course.

Let's compare the percentage of unarmed shot for each race.

e) What percent are White and Unarmed?

f) What percent are Hispanic and Unarmed?

If you compare answers d, e and f it shows the highest percentage of unarmed people being shot is most likely white.

Why is that?

This is because there are more white people in the United States than any other race and therefore there are likely to be more white people in the table. Since there are more white people in the table, there most likely would be more white and unarmed people shot by police than any other race. This pulls the percentage of white and unarmed up. In addition, there most likely would be more white and armed shot by police. All the percentages for white people would be higher, because there are more white people. For example, the table contains very few Hispanic people, and the percentage of people in the table that were Hispanic and unarmed is the lowest percentage.

Think of it this way. If you went to a college that was 90% female and 10% male, then females would most likely have the highest percentage of A grades. They would also most likely have the highest percentage of B, C, D and F grades

The correct way to compare is "conditional probability". Conditional probability is getting the probability of something happening, given we are dealing with just the people in a particular group.

g) What percent of blacks shot and killed by police were unarmed?

h) What percent of whites shot and killed by police were unarmed?

i) What percent of Hispanics shot and killed by police were unarmed?

You can see by the answers to part g and h, that the percentage of blacks that were unarmed and killed by police is approximately twice that of whites that were unarmed and killed by police.

j) Why do you believe this is happening?

Do a search on the internet for reasons why blacks are more likely to be killed by police. Read a few articles on the topic. Write your response using the articles as references. Give the websites used in your response. Your answer should be several sentences long with at least one website listed. This part of this problem will be graded after the due date.

Suspect was Armed:

Black - 543

White - 1176

Hispanic - 378

Total - 2097

Suspect was unarmed:

Black - 60

White - 67

Hispanic - 38

Total - 165

Total:

Black - 603

White - 1243

Hispanic - 416

Total - 2262

Give your answer as a decimal to at least three decimal places.

a) What percent are Black?

b) What percent are Unarmed?

c) In order for two variables to be Independent of each other, the P \((A and B) = P(A) \cdot P(B) P(A and B) = P(A) \cdot P(B).\)

This just means that the percentage of times that both things happen equals the individual percentages multiplied together (Only if they are Independent of each other).

Therefore, if a person's race is independent of whether they were killed being unarmed then the percentage of black people that are killed while being unarmed should equal the percentage of blacks times the percentage of Unarmed. Let's check this. Multiply your answer to part a (percentage of blacks) by your answer to part b (percentage of unarmed).

Remember, the previous answer is only correct if the variables are Independent.

d) Now let's get the real percent that are Black and Unarmed by using the table?

If answer c is "significantly different" than answer d, then that means that there could be a different percentage of unarmed people being shot based on race. We will check this out later in the course.

Let's compare the percentage of unarmed shot for each race.

e) What percent are White and Unarmed?

f) What percent are Hispanic and Unarmed?

If you compare answers d, e and f it shows the highest percentage of unarmed people being shot is most likely white.

Why is that?

This is because there are more white people in the United States than any other race and therefore there are likely to be more white people in the table. Since there are more white people in the table, there most likely would be more white and unarmed people shot by police than any other race. This pulls the percentage of white and unarmed up. In addition, there most likely would be more white and armed shot by police. All the percentages for white people would be higher, because there are more white people. For example, the table contains very few Hispanic people, and the percentage of people in the table that were Hispanic and unarmed is the lowest percentage.

Think of it this way. If you went to a college that was 90% female and 10% male, then females would most likely have the highest percentage of A grades. They would also most likely have the highest percentage of B, C, D and F grades

The correct way to compare is "conditional probability". Conditional probability is getting the probability of something happening, given we are dealing with just the people in a particular group.

g) What percent of blacks shot and killed by police were unarmed?

h) What percent of whites shot and killed by police were unarmed?

i) What percent of Hispanics shot and killed by police were unarmed?

You can see by the answers to part g and h, that the percentage of blacks that were unarmed and killed by police is approximately twice that of whites that were unarmed and killed by police.

j) Why do you believe this is happening?

Do a search on the internet for reasons why blacks are more likely to be killed by police. Read a few articles on the topic. Write your response using the articles as references. Give the websites used in your response. Your answer should be several sentences long with at least one website listed. This part of this problem will be graded after the due date.

asked 2020-11-09

The two-way table summarizes data on the gender and eye color of students in a college statistics class. Imagine choosing a student from the class at random. Define event A: student is male and event B: student has blue eyes.

\(\begin{array}{c|cc|c} &\text{Male}&\text{Female}&\text{Total}\\ \hline \text{Blue}&&&10\\ \text{Brown}&&&40\\ \hline \text{Total}&20&30&50 \end{array}\\)

Copy and complete the two-way table so that events A and B are mutually exclusive.

\(\begin{array}{c|cc|c} &\text{Male}&\text{Female}&\text{Total}\\ \hline \text{Blue}&&&10\\ \text{Brown}&&&40\\ \hline \text{Total}&20&30&50 \end{array}\\)

Copy and complete the two-way table so that events A and B are mutually exclusive.

asked 2021-01-31

Use the two-way table below to answer the following question. Round the answer to the nearest whole percent. There are 300 seniors at Bellmere Senior High School who are enrolled in elective science classes as shown below.

\(\begin{array}{c|cc|c} &\text{Physics}&\text{Chemistry}&\text{Total}\\ \hline \text{Males}&100&68&168\\ \text{Females}&71&61&132\\ \hline \text{Total}&171&129&300 \end{array}\\)

What is the probability that a senior student chosen at random is enrolled in physics given that student is female?

\(\begin{array}{c|cc|c} &\text{Physics}&\text{Chemistry}&\text{Total}\\ \hline \text{Males}&100&68&168\\ \text{Females}&71&61&132\\ \hline \text{Total}&171&129&300 \end{array}\\)

What is the probability that a senior student chosen at random is enrolled in physics given that student is female?

asked 2021-01-19

A survey of 4826 randomly selected young adults (aged 19 to 25 ) asked, "What do you think are the chances you will have much more than a middle-class income at age 30? The two-way table summarizes the responses.

\(\begin{array} {c|cc|c} & \text { Female } & \text { Male } & \text { Total } \\ \hline \text { Almost no chance } & 96 & 98 & 194 \\ \hline \text { Some chance but probably not } & 426 & 286 & 712 \\ \hline \text { A 50-50 chance } & 696 & 720 & 1416 \\ \hline \text { A good chance } & 663 & 758 & 1421 \\ \hline \text { Almost certain } & 486 & 597 & 1083 \\ \hline \text { Total } & 2367 & 2459 & 4826 \end{array}\)

Choose a survey respondent at random. Define events G: a good chance, M: male, and N: almost no chance. Given that the chosen student didn't say "almost no chance," what's the probability that this person is female? Write your answer as a probability statement using correct symbols for the events.

\(\begin{array} {c|cc|c} & \text { Female } & \text { Male } & \text { Total } \\ \hline \text { Almost no chance } & 96 & 98 & 194 \\ \hline \text { Some chance but probably not } & 426 & 286 & 712 \\ \hline \text { A 50-50 chance } & 696 & 720 & 1416 \\ \hline \text { A good chance } & 663 & 758 & 1421 \\ \hline \text { Almost certain } & 486 & 597 & 1083 \\ \hline \text { Total } & 2367 & 2459 & 4826 \end{array}\)

Choose a survey respondent at random. Define events G: a good chance, M: male, and N: almost no chance. Given that the chosen student didn't say "almost no chance," what's the probability that this person is female? Write your answer as a probability statement using correct symbols for the events.

asked 2021-01-22

A county is populated with 20,899,000 people, while the population is growing at a rate of 3.2% per year. What will the population be in 19 years? Round the answer to the nearest thousand.